 (defn initialize-element [set-registry element]
   (update-in set-registry [:element-map element] #(or % empty-element-entry)))
 
-(defn initialize-set [set-registry set-id]
-  (update-in set-registry [:set-map set-id] #(or % empty-set-entry)))
-
 (defn register-membership [set-registry element set-id]
   (-> set-registry
       (update-in [:element-map element :set-ids] #(conj % set-id))))

               (clojure.set/union (rest unseen-sets) supersets-of-first)
               seen-sets)))))))

(defn add-superset-generator-sub [set-registry key generator]
  (update set-registry :generators #(assoc % key generator)))


   clojure.set/union
   #{}
   (:generators set-registry)))



(declare subset-of)
